Abstract 389: Focal adhension kinase (FAK) confers lenvatinib resistance in hepatocellular carcinoma via regulation of lysine deficient protein kinase 1(WNK1)

Abstract Lenvatinib is a clinically effective multi-kinase inhibitor approved for first-line therapy of advanced hepatocellular carcinoma (HCC). Although resistance against lenvatinib often emerges and limits its anti-tumor activity, the underlying molecular mechanisms involved in endogenous and acquired resistance are still unidentified. Endogenous (SNU449 and SNU475) and established acquired (Hep3B-LR and Huh7-LR) lenvatinib resistant cells, as well as knockout mice were used in this study. As a result, we recognized focal adhension kinase (FAK) as a critical contributor to lenvatinib resistance in HCC. The elevated expression of FAK was observed in both established and endogenous lenvatinib-resistant HCC cells. Furthermore, inhibition of FAK reversed lenvatinib resistance in vitro and in vivo. Mechanistically, FAK promoted lenvatinib resistance through regulating lysine deficient protein kinase 1 (WNK1) signaling pathway. WNK1 inhibitor WNK463 re-sensitized either established LR HCC cells (Hep3B-LR and Huh7-LR) or endogenous resistant HCC cells (SNU449 and SNU475) to lenvatinib treatment. In addition, overexpression of WNK1 desensitized parental HCC cells (Hep3B-P and Huh7-P) to lenvatinib treatment. Conclusively, our results establish a crucial role and novel mechanism of FAK in lenvatinib resistance, and suggest that targeting the FAK/WNK1 axis is a promising therapeutic strategy in HCC patients showing lenvatinib resistance. Citation Format: Wei Hou, Shaimaa A. Gad, Wei Qiu. Focal adhension kinase (FAK) confers lenvatinib resistance in hepatocellular carcinoma via regulation of lysine deficient protein kinase 1(WNK1) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 389.